About exposure zone with slides and prints.

[dennis_j_smith]

I have read several of your answers to other question that touch this topic. I attended a John Shaw workshop that discussed color exposure and zones which is line with your answers, so I think you can help me here John Shaw dose not answer E-mail.

 

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I work with print film, and now starting to shoot with slides. To get nice color of a rainbow with print film, I would over expose by 1~1 2/3 stops, I assume that slides would be the oposite, underexpose by 1~1 1/2 stops. I'm a bit confused with the zone aspect of exposure for slides, that is if the color you are meetering is light blue, exposure would be what the meter suggested +1 stop. Dose this mean open the appature by one stop? Is this +1 the oposite for prints. I'm am just trying to bring this together in my confused mind. Thanks In advance, Dennis

[bob_atkins]

Slides have a total dynamic range of about 5 stops. That means

anything 2.5 stops or more darker than a mid tone will be black,

and anything 2.5 or more stops lighter than a mid tone will be

white [assuming you expose for a mid tone].

 

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If you see an area you want to reproduce as light blue, and you

meter on it, the meter will give an exposure which would make

that area a mid tone - which isn't what you want. In order to make

it <em>light</em> blue, you have to give it <em>more</em> exposure, e.g.

+1 stop. That means that if the camera suggests 1/125 at f8, you

would shoot at 1/125 at f5.6 (or 1/60 at f8).

 

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Underexposing tends to saturate colors when using slide film, so slightly underexposing

a rainbow would be appropriate. However with slide film, a 1.5

stop underexposure would be getting pretty dark. Perhaps 0.5 to

1 stop underexposure would be appropriate (preferably shoot

both!).

 

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Print film has a wider dynamic range (latitude) than slide film,

so you can under or overexpose to a greater extent and still get

good images. You can also compensate during printing, which, of

course, you can't do with a 1st generation image like a slide,

which is why it is much more important to get expsoure correct

for slide film than for print film.

[dennis_j_smith]

So to further my understanding, just to cossreferance, the exposure scall would be med-blue = meter, lt blue = +1, lt lt blue = +2, real lt blue with no detail = +2.5 would be for slides and this would be the oposite for prints/negs ie med-blue = meter, lt blue = -1, lt lt blue = -2 and so forth?

 

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And again, thanks for your patiants

[glen_johnson]

As Bob points out, the range for slide film is a whole lot smaller than the range for print film. If you want to think in terms of zones, you need to rethink what constitutes a zone. It is not a whole stop with slides. It is more like a half a stop. By the time you've gone to +2.5, you are washed out. By the time you've gone to -2.5 you're in the black. It really doesn't matter a whole lot what color you've started with. Slide film is very unforgiving compared to print film. At the same time, if you've got a decent meter (hand held or on camera) and if you're reasonably alert, you can handle it.

[bobatkins]

In response to Dennis, your comments on slide exposure are correct,

but once you get to +2.5 and more you tend to get just bleached

out film (clear = white) rather than featureless light color.

 

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As for print film, I never use it for serious photography, so

I can't really comment with authority! I

assume that much what determins whether blue comes out medium. light

or dark is in the printing step, not the exposure itself. Since

the negative can hold detail over a range of maybe 8 stops, you

just don't need to be quite so critical when it comes to exposure.

Unless you are using a custom lab, whatever exposure you use, the

lab will adjust the printing to give you a mid-tone, i.e. they

balance a whole print to an average mid-tone. This is done

automatically I think in most high volume consumer labs. You

might get <em>some</em> differences if you adjust exposure, but

nowhere near the differences you see on slide film.

[scott_t._lavender]

I basically agree with the responses posted so far. But, I think that everyone is ignoring a basic misconception that you have regarding exposure of 'positive' vs 'negative' film.

 

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If you want to render a blue subject as a light blue tone you would increase the exposure, using either print or slide film. The only difference would be the amount of increase.

 

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In my experience the range from 'black' to 'white' in slide film is five(5) stops as others have stated. For color print film the range is seven(7) to eight(8) stops. B&W film can record a range up to ten(10) stops.

 

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When using color slide film, I use 1/2 stop increments for each stop/zone of exposure change required to render a subject as a tone other than 18% grey or Zone V. Alternatly, I use a one(1) stop/zone change in exposure when using color print film. In the case of color slide film it is also a good idea to bracket the shot.

 

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So, the blue subject that you want to render as a light blue tone should be metered first. Then, the base exposure should be increased by 1/2 stop for color slide film and by one(1) stop for color print film. This should give you the results that you desire.

 

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I hope that this discussion helps!

 

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Later.....Scott...

[bahman_farzad]

Dear Dennis, You got a great response from Bob Atkins. It is very accurate and he knows exactly what he is talking about. I just wanted to add a couple of things. About 70% of my work is with slides, about 20% color negative and 10% black and white. I think and live color slides and expose for color slides. One is always safe going from slides to negatives. Going the other way (as you are doing) is not as easy because you are not as diciplined and as established. People can make many mistakes with color negatives and never know about them. With color slides, �what you take is what you get� With color negatives, what you eventually get is not what you took but what you were given. In other words �what you take is not necessarily what you get.� Therefore I would give you one piece of advice: All this overexposing lowlights (shadows) and all the other stuff is the 1940�s and 1950�s mentality where everybody processed their negative films and enlarged them. In the 1990s where more than 95% of all outdoor photography is in color, very few people enlarge and process their own the idea is clichi. Learn how to expose slides, master the art of exposure (don�t bracket since habitual bracketing is the sign of ignorance of light and exposure). Once you did that, the only thing that you know should be the ISO of your film and go for it. Good luck. PS: I have written a book about On-camera spotmetering. It uses the five-tone zone system (very much like John Shaw) that I have been teaching for the past 20 years. It is called �The Confused Photographer�s Guide to On-Camera Spotmetering� ISBN:0966081706. It is slide based and will help you a lot. Look into barnesandnoble.com, it should be there.